HENRY I
in a sufficiently strong position easily to crush a rebellion of his own barons in favour of Duke Robert that broke out in 1102. While he was thus consolidating his power at home he induced the penurious Robert, who had found crusading an expensive occupation, to drop his claims in England in return for a small financial consideration ; needless to say, he had every intention of bringing the dispute to a far more satisfactory and permanent conclusion as soon as he should be in a position to resume hostilities. His organizing ability was such that he had not long to wait and in 1106 he invaded Normandy and completely defeated his brother at the battle of Tenchebrai and brought the unfortunate Duke back to England where he kept him in close confinement until his death many years later. Despite the fact that Robert's son, William Clito, continued, with the aid of the French King, to uphold his father's rights until his death in 1128 and kept the Norman frontiers in a constant state of alarm, Henry's dominions were never again in serious danger of invasion. Having settled his affairs on the continent Henry now turned his attention to Wales, where the Normans had hitherto been unable to penetrate very far. He now conquered the southern part of that country where he built numerous castles and installed a large colony of industrious Flemings.
About this time Henry's happiness was shattered by a tragedy in his own family. His only son William was drowned in a storm while returning from Normandy to England, and Henry was faced with the gloomy prospect of being succeeded in a realm which, although
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